Twenty-One at TREC-8: using Language Technology for Information Retrieval

This paper describes the official runs of the Twenty-One group for TREC-8. The Twenty-One group participated in the Ad-hoc, CLIR, Adaptive Filtering and SDR tracks. The main focus of our experiments is the development and evaluation of retrieval methods that are motivated by natural language processing techniques. The following new techniques are introduced in this paper. In the Ad-Hoc and CLIR tasks we experimented with automatic sense disambiguation followed by query expansion or translation. We used a combination of thesaurial and corpus information for the disambiguation process. We continued research on CLIR techniques which exploit the target corpus for an implicit disambiguation, by importing the translation probabilities into the probabilistic term-weighting framework. In filtering we extended the use of language models for document ranking with a relevance feedback algorithm for query term reweightin

HaploReg: a resource for exploring chromatin states, conservation, and regulatory motif alterations within sets of genetically linked variants

The resolution of genome-wide association studies (GWAS) is limited by the linkage disequilibrium (LD) structure of the population being studied. Selecting the most likely causal variants within an LD block is relatively straightforward within coding sequence, but is more difficult when all variants are intergenic. Predicting functional non-coding sequence has been recently facilitated by the availability of conservation and epigenomic information. We present HaploReg, a tool for exploring annotations of the non-coding genome among the results of published GWAS or novel sets of variants. Using LD information from the 1000 Genomes Project, linked SNPs and small indels can be visualized along with their predicted chromatin state in nine cell types, conservation across mammals and their effect on regulatory motifs. Sets of SNPs, such as those resulting from GWAS, are analyzed for an enrichment of cell type-specific enhancers. HaploReg will be useful to researchers developing mechanistic hypotheses of the impact of non-coding variants on clinical phenotypes and normal variation. The HaploReg database is available at http://compbio.mit.edu/HaploReg.National Institutes of Health (U.S.) (R01-HG004037)National Institutes of Health (U.S.) (RC1-HG005334)National Science Foundation (U.S.) (HG005334

Profits, Welfare, and Class Position: 1965-1984

The study utilizes an extended version of a Charles V Hamilton paradigm in order to estimate yearly income transfers between classes in America\u27s system of welfare state capitalism. Analyzing the period from 1965 to 1984, what becomes most obvious is the substantial annual transfer from the middle/working class to the owning class. The transfer rose to more than $150 billion by 1984-a full 10% of middle/ working class income. Yet when looking at the implications, an interesting paradox emerges. Although the amount of transfer has increased some over the period, it has not grown nearly as fast as the after-tax income gap between the two classes. Those at the top have gotten sizably richer, while those beneath them have actually been witnessing a real-dollar income decline. Ultimately, this is attributed to both a postindustrial income bimodality within the non-elite population as well as a redistribution downward within that group. Frustrated by their own declining economic status, however, middle Americans at least temporarily turn a good bit of their wrath towards welfare recipients and not the owners of capital-much as Hamilton predicted

Profits, Welfare, and Class Position: 1965-1984

The study utilizes an extended version of a Charles V Hamilton paradigm in order to estimate yearly income transfers between classes in America\u27s system of welfare state capitalism. Analyzing the period from 1965 to 1984, what becomes most obvious is the substantial annual transfer from the middle/working class to the owning class. The transfer rose to more than $150 billion by 1984-a full 10% of middle/ working class income. Yet when looking at the implications, an interesting paradox emerges. Although the amount of transfer has increased some over the period, it has not grown nearly as fast as the after-tax income gap between the two classes. Those at the top have gotten sizably richer, while those beneath them have actually been witnessing a real-dollar income decline. Ultimately, this is attributed to both a postindustrial income bimodality within the non-elite population as well as a redistribution downward within that group. Frustrated by their own declining economic status, however, middle Americans at least temporarily turn a good bit of their wrath towards welfare recipients and not the owners of capital-much as Hamilton predicted

Technology, Corporate Mobility, and a Decline in Urban Services

Technological changes have produced a postindustrial economy which has both facilitated and encouraged the flight of capital and well-to-do people from the older industrial cities. Left in their wake are increasing levels of unemployment, poverty, and crime. Service needs have Increased accordingly, but at a time when these cities have not only smaller tax bases but also less electoral clout with which to acquire additional financial assistance at the state and federal levels. In a nearly futile attempt to reestablish a healthy degree of private investment in their cities, municipal governments let service levels decline and focus on spurring capital accumulation

Sistema sulco/camalhão para irrigação e drenagem em áreas de várzea.

SISTEMA SULCO/CAMALHÃO PARA IRRIGAÇÃO E DRENAGEM EM ÁREAS DE VÁRZEA - A soja e o milho são as principais culturas produtoras de grãos utilizadas na diversificação do sistema de produção nas várzeas do Rio Grande do Sul, em rotação com o arroz irrigado. Os principais fatores limitantes, para que estas culturas sejam produtivas e rentáveis neste sistema, são a deficiente drenagem natural do solo e a ocorrência de freqüentes períodos de estiagem, acarretando alternância entre o excesso e o déficit de umidade no solo. A Embrapa Clima Temperado testou e validou a técnica sulco/camalhão em áreas sistematizadas com e sem declive, para estes cultivos, com resultados bastante promissores. O sistema consiste na estruturação da lavoura para a irrigação por sulcos, obtendo-se, ao mesmo tempo, grande benefício em drenagem, com o cultivo sobre os camalhões formados entre os sulcos. Esta técnica, como sistema complementar de drenagem superficial do solo, mostrou-se muito eficiente mesmo nos cultivos em áreas sistematizadas sem declive, onde não existe um gradiente para escoamento superficial da água. O principal requisito para a irrigação por sulcos é que o terreno tenha uma declividade constante e uniforme, requerendo geralmente a sistematização do terreno. Para irrigações mais uniformes e eficientes, a declividade deve variar de 0,10% a 0,50%, sendo que valores intermediários entre 0,15% e 0,30% são os mais indicadosbitstream/item/31294/1/comunicado-165.pd

Predictability of the quasi-biennial oscillation and its northern winter teleconnection on seasonal to decadal timescales

Journal ArticlePublished version used with permision of the publisher.The predictability of the quasi-biennial oscillation (QBO) is examined in initialized climate forecasts extending out to lead times of years. We use initialized retrospective predictions made with coupled ocean-atmosphere climate models that have an internally generated QBO. We demonstrate predictability of the QBO extending more than 3 years into the future, well beyond timescales normally associated with internal atmospheric processes. Correlation scores with observational analyses exceed 0.7 at a lead time of 12 months. We also examine the variation of predictability with season and QBO phase and find that skill is lowest in winter. An assessment of perfect predictability suggests that higher skill may be achievable through improved initialization and climate modeling of the QBO, although this may depend on the realism of gravity wave source parameterizations in the models. Finally, we show that skilful prediction of the QBO itself does not guarantee predictability of the extratropical winter teleconnection that is important for surface winter climate prediction. Key Points The QBO is skilfully predicted in seasonal-decadal forecast systems Further improvements in predictions of the QBO are possible The QBO winter surface teleconnection is reproduced with mixed succes

Conserved presence of G-quadruplex forming sequences in the Long Terminal Repeat Promoter of Lentiviruses

G-quadruplexes (G4s) are secondary structures of nucleic acids that epigenetically regulate cellular processes. In the human immunodeficiency lentivirus 1 (HIV-1), dynamic G4s are located in the unique viral LTR promoter. Folding of HIV-1 LTR G4s inhibits viral transcription; stabilization by G4 ligands intensifies this effect. Cellular proteins modulate viral transcription by inducing/unfolding LTR G4s. We here expanded our investigation on the presence of LTR G4s to all lentiviruses. G4s in the 5'-LTR U3 region were completely conserved in primate lentiviruses. A G4 was also present in a cattle-infecting lentivirus. All other non-primate lentiviruses displayed hints of less stable G4s. In primate lentiviruses, the possibility to fold into G4s was highly conserved among strains. LTR G4 sequences were very similar among phylogenetically related primate viruses, while they increasingly differed in viruses that diverged early from a common ancestor. A strong correlation between primate lentivirus LTR G4s and Sp1/NF\u3baB binding sites was found. All LTR G4s folded: their complexity was assessed by polymerase stop assay. Our data support a role of the lentiviruses 5'-LTR G4 region as control centre of viral transcription, where folding/unfolding of G4s and multiple recruitment of factors based on both sequence and structure may take place

Use of groundwater lifetime expectancy for the performance assessment of a deep geologic waste repository: 1. Theory, illustrations, and implications

Long-term solutions for the disposal of toxic wastes usually involve isolation of the wastes in a deep subsurface geologic environment. In the case of spent nuclear fuel, if radionuclide leakage occurs from the engineered barrier, the geological medium represents the ultimate barrier that is relied upon to ensure safety. Consequently, an evaluation of radionuclide travel times from a repository to the biosphere is critically important in a performance assessment analysis. In this study, we develop a travel time framework based on the concept of groundwater lifetime expectancy as a safety indicator. Lifetime expectancy characterizes the time that radionuclides will spend in the subsurface after their release from the repository and prior to discharging into the biosphere. The probability density function of lifetime expectancy is computed throughout the host rock by solving the backward-in-time solute transport adjoint equation subject to a properly posed set of boundary conditions. It can then be used to define optimal repository locations. The risk associated with selected sites can be evaluated by simulating an appropriate contaminant release history. The utility of the method is illustrated by means of analytical and numerical examples, which focus on the effect of fracture networks on the uncertainty of evaluated lifetime expectancy.Comment: 11 pages, 8 figures; Water Resources Research, Vol. 44, 200

Dynamics of Decadal Climate Variability and Implications for its Prediction

The temperature record of the last 150 years is characterized by a long-term warming trend, with strong multidecadal variability superimposed. The multidecadal variability is also seen in other (societal important) parameters such as Sahel rainfall or Atlantic hurricane activity. The existence of the multidecadal variability makes climate change detection a challenge, since Global Warming evolves on a similar timescale. The ongoing discussion about a potential anthropogenic signal in the Atlantic hurricane activity is an example. A lot of work was devoted during the last years to understand the dynamics of the multidecadal variability, and external as well as internal mechanisms were proposed. This White Paper focuses on the internal mechanisms relevant to the Atlantic Multidecadal Oscillation/Variability (AMO/V) and the Pacific Decadal Oscillation/Variability (PDO/V). Specific attention is given to the role of the Meridional Overturning Circulation (MOC) in the Atlantic. The implications for decadal predictability and prediction are discussed